import java.lang.reflect.Array;

public class Test {
    public static void main(String[] args){
        Singleton s1 = Singleton.getInstance();
        Singleton s2 = Singleton.getInstance();

        if (s1==s2){
            System.out.println("s1=s2");
        }else {
            System.out.println("s1!=s2");
        }


        Singleton2 s3 = Singleton2.getInstance();
        Singleton2 s4 = Singleton2.getInstance();

        if (null == s3){
            System.out.println("空");
        }else{
            System.out.println("非空");
        }
    }

}
